St. Patrick's Day Event - How does the MAX button work?
Using the Max button shows you the maximum number of levels (and cost) you can upgrade from the gathered Shamrocks, rather than upgrading one level at a time. If the Max checkbox is activated, but you don't have enough shamrocks for the upgrade, there will be a +1 and the cost for it, but grayed out, as you do not yet have enough shamrocks.
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